The term stone age was coined in the late nineteenth century CE by the Danish scholar Christian J Thomsen, who came up with the frame work for the study of human past, known as the 'Three age system' . Thye bassis of this framework is technological; it revolves around the notion of three sucessive periods or ages; Stone age, Bronze age, and the Iron age, each age being technologically more complex than the one before. Thomsen came up with this idea after noticing that the material taht they were made with; stone made tools were always found in the deepest layers, bronze artifacts in layers on top of the deepest layers, and finally iron made artefacts were found closest to the surface. This sugessted that matel technology develped later tahn stone made tools.
